You can't get hiv when you used a condom, plus if he always uses one that would mean he is negative. You should move on from this non-event and not discuss it with your wife since there is no risk to her. There is no useful hiv diagnostic info on Google anyway because only tests can be used to determine if a person is positive which is why he tested instead of googling.
You used a condom which did NOT come off and did NOT break. As you said yourself "it was intact," therefore you had PROTECTED SEX, which is SAFE SEX and as both GuitarRox and AnxiousNoMore told you that means you had NO RISK for HIV. You also asked "What if he isn't negative?" Doesn't matter what his status is. You had protected sex....you are safe, you had no risk. And you really gotta let this go. Resume sex with your wife knowing you are clean. You also asked "Why do you take PrEP if you're negative." GuitarRox gave you the answer.....I'll just rephrase it. You take PrEP if you're negative and want to STAY NEGATIVE.
The one question you asked that didn't get addressed and I believe it's a VERY important one.......you asked "Do you think people lie about their status?" I have absolutely no doubt there ARE people out there who lie about their status. To go into the REASONS they lie is far beyond the scope of this forum. The only recourse for ANY of us, regardless of which team we bat for, is to ALWAYS, ALWAYS use a condom for penetrative sex.